From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5E22E8FDC2 for ; Wed, 4 Oct 2023 00:49:23 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 61C3F8D008E; Tue, 3 Oct 2023 20:49:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5CC398D0003; Tue, 3 Oct 2023 20:49:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 494A38D008E; Tue, 3 Oct 2023 20:49:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 370078D0003 for ; Tue, 3 Oct 2023 20:49:23 -0400 (EDT) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id E62BC804D5 for ; 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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 3C479100005 X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: 7zp638xbu3caoxhgtysd9jgxopfbpsnq X-HE-Tag: 1696380560-642422 X-HE-Meta: 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 oui7a5Xb 1V8prZ3fSBYhEVDMkEvNHnuEC3iTtsERG0AXXCxzoHxY1EqB9s+0PYE6sQW5NBoWrspjkus3ZwE98bBbgWYPCcwOf390ZFVPUhyJpseotIscERf0GqM34/U6aLI6BCM1fEm85IzUGVztWH2uYXik51W530jGmgtBwWjYlzEV+V/pg1LZrdG+skHZE59LEslEjAhjGNp2+N1BQzL7efEvlPzve+jXZ+5aXpIttyTI3zxZh1bXMwVclDTmvgX9fF7TZs2Gcs/60OmNKb6vsLx5OdWMFeOwu8sTM5aODIKqXENACheQnv2yCH5LzRbstqrmTw4hdoEPypJjwi0Tve3PryuG0poDi5kFongVNYtOs2GjW68ktznotJKTDqg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 13 Sep 2023 02:20:49 +0000 SeongJae Park wrote: > DAMON provides damon_aggregated tracepoint, which exposes details of > each region and its access monitoring results. It is useful for > getting whole monitoring results, e.g., for recording purposes. >=20 > For investigations of DAMOS, DAMON Sysfs interface provides DAMOS > statistics and tried_regions directory. But, those provides only > statistics and snapshots. If the scheme is frequently applied and if > the user needs to know every detail of DAMOS behavior, the > snapshot-based interface could be insufficient and expensive. >=20 > As a last resort, userspace users need to record the all monitoring > results via damon_aggregated tracepoint and simulate how DAMOS would > worked. It is unnecessarily complicated. DAMON kernel API users, > meanwhile, can do that easily via before_damos_apply() callback field of > 'struct damon_callback', though. >=20 > Add a tracepoint that will be called just after before_damos_apply() > callback for more convenient investigations of DAMOS. The tracepoint > exposes all details about each regions, similar to damon_aggregated > tracepoint. >=20 > Please note that DAMOS is currently not only for memory management but > also for query-like efficient monitoring results retrievals (when 'stat' > action is used). Until now, only statistics or snapshots were > supported. Addition of this tracepoint allows efficient full recording > of DAMOS-based filtered monitoring results. >=20 =46rom a tracing point of view. Reviewed-by: Steven Rostedt (Google) -- Steve